Surge control system for managed pressure drilling operations

ABSTRACT

A managed pressure drilling (MPD) system includes a work string having one or more tubulars having an internal flow path. The work string supports a liner string terminating in a liner float. A liner hanger running tool is coupled to the work string uphole of the liner string and the liner float. A selectively operable surge control sub is arranged uphole of the liner hanger running tool, and a selectively operable MPD sub is positioned uphole of the liner hanger running tool and the selectively operable surge control sub. The selectively operable MPD sub is operable to close off the internal flow path to fluid pressure passing uphole from the liner float in a first position during MPD operations and opens the internal flow path to fluid pressure after the liner string reaches a target depth.

BACKGROUND

In the resource recovery industry managed pressure drilling is oftenused in order to reduce forces on a formation. During a managed pressuredrilling (MPD) operation, drillers manage wellbore pressure constrainedby formation property limits. Annular pressure is maintained slightlyabove pore pressure to prevent an influx of formation fluids into thewellbore and below fracture pressure by using hydrostatic pressurecreated by the wellbore fluid combined with added applied pressure downthe annulus to create a downhole combined pressure that exceeds porepressure, but stays below fracture gradient. The applied pressure downthe annulus, if left unchecked, will force fluid up the work string andonto the drill floor/top drive/mud handling system.

Currently, fluid flow up the work string is controlled by utilizing adrill-pipe float check valve during drilling operations and casing floatduring casing operations. It is desirable to control surge pressureduring an MPD operation in order to prevent fracturing/damaging the openformation in the well bore. With conventional liner running operations,the use of a conventional casing float places undesirable stresses onthe formation due to a large volume of fluid that is being displaced bythe casing. In addition, the passing drill pipe through the casingcreates an additional source of increased pressure.

Formation surface effects create stresses on the formation that couldlead to undesirable fracture gradient breakdown. While running casingwith an active MPD system, there is a need to reduce formation surgeeffects while, at the same time, prevent mud from being pushed up thedrillstring. Accordingly, the industry would be open to a system forreducing surge effects during an MPD operation.

SUMMARY

Disclosed is a managed pressure drilling (MPD) system including a workstring having one or more tubulars having an internal flow path. Thework string supporting a liner string terminating in a liner float. Aliner hanger running tool is coupled to the work string uphole of theliner string and the liner float. A selectively operable surge controlsub is arranged uphole of the liner hanger running tool, and aselectively operable MPD sub is positioned uphole of the liner hangerrunning tool and the selectively operable surge control sub. Theselectively operable MPD sub is operable to close off the internal flowpath to fluid pressure passing uphole from the liner float in a firstposition during MPD operations and opens the internal flow path to fluidpressure after the liner string reaches a target depth.

Also disclosed is a resource exploration and recovery system including asurface system having a managed pressure drilling controller. A hostcasing extends downhole into a wellbore. A subsurface system includes awork string extending from the surface system through the host casinginto the wellbore. The work string includes one or more tubulars havingan internal flow path, the work string including a liner string and aliner float. A liner hanger running tool is coupled to the work stringuphole of the liner string and the liner float. A selectively operablesurge control sub is arranged uphole of the liner hanger running tool. Aselectively operable MPD sub is positioned uphole of the liner hangerrunning tool and the selectively operable surge control sub. Theselectively operable MPD sub is operable to close off the internal flowpath to fluid pressure passing uphole from the liner float in a firstposition during MPD operations and opens the internal flow path to fluidpressure after the liner string reaches a target depth.

Further disclosed is a method of performing a managed pressure drilling(MPD) operation including performing surge reduction activities during amanaged pressure drilling (MPD) operations with an MPD system supportedon a work string including a liner hanger running tool, a selectivelyoperable surge control sub, and a selectively operable MPD sub arrangeduphole of a liner string, allowing fluid to freely flow through theliner string into the liner hanger running tool, dissipating surgepressure via the selectively operable surge control sub positioned belowthe selectively operable MPD sub without returning fluid up the workstring, and opening the selectively operable MPD sub and closing theselectively operable surge control valve after the liner string hasreached a target depth.

BRIEF DESCRIPTION OF THE DRAWINGS

The following descriptions should not be considered limiting in any way.With reference to the accompanying drawings, like elements are numberedalike:

FIG. 1 depicts a resource exploration and recovery system having amanaged pressure drilling (MPD) system, including an MPD sub, a surgecontrol valve, and a liner hanger running tool, in accordance with anexemplary embodiment;

FIG. 2A depicts a first portion of a work string supporting the MPD sub,surge control valve and liner hanger running tool, in accordance with anexemplary aspect;

FIG. 2B depicts a second portion of the work string of FIG. 2A;

FIG. 2C depicts a third portion of the work string of FIG. 2A;

FIG. 3 depicts the MPD sub in a closed configuration for lowering aliner to a target depth, in accordance with an exemplary aspect; and

FIG. 4 depicts the MPD sub of FIG. 3 in an open configuration for postMPD operations, in accordance with an exemplary aspect.

DETAILED DESCRIPTION

A detailed description of one or more embodiments of the disclosedapparatus and method are presented herein by way of exemplification andnot limitation with reference to the Figures.

A resource exploration and recovery system, in accordance with anexemplary embodiment, is indicated generally at 10, in FIG. 1. Resourceexploration and recovery system 10 should be understood to include welldrilling operations, completions, resource extraction and recovery, CO₂sequestration, and the like. Resource exploration and recovery system 10may include a first system 14 which, in some environments, may take theform of a surface system 16 operatively and fluidically connected to asecond system 18 which, in some environments, may take the form of asubsurface or downhole system (not separately labeled).

First system 14 may include a control system 23 that may provide powerto, monitor, communicate with, and/or activate one or more downholeoperations as will be discussed herein. Surface system 16 may includeadditional systems such as pumps, fluid storage systems, cranes and thelike (not shown).

Second system 18 includes a work string 30 that extends into a wellbore34 formed in a formation 36. Work string 30 may take the form of amanaged pressure drilling (MPD) string 38 formed from a plurality ofinterconnected tubulars, one of which is indicated at 40. Wellbore 34includes an annular wall 42 which may be defined by a surface offormation 36. A host casing 48 extends from first system 14 in adownhole direction. Work string 30 passes through host casing 48 and, aswill be detailed herein, supports a liner string 50 that terminates in aliner float 52.

In an embodiment illustrated in FIGS. 2A-2C, work string 30 includes aninternal flow path 54 that is fluidically connected to a managedpressure drilling (MPD) system 58. Internal flow path 54 extends throughwork string 30 from a liner hanger running tool 62 that is operable toinstall liner string 50 inside wellbore 34. Work string 30 also includesa selectively operable surge control valve 64 and a selectively operableMPD sub 66 arranged uphole of liner hanger running tool 62 within hostcasing 48. As will be detailed more fully herein, a selectively operablesurge control valve 64 is positioned between selectively operable MPDsub 66 and liner hanger running tool 62. Selectively operable MPD sub 66is operable to dissipate surge pressure during MPD operations. That is,selectively operable MPD sub 66 substantially prevents fluid pressuregenerated from MPD system 58 from passing uphole via internal flow path54 to surface system 16.

In an embodiment illustrated in FIGS. 3 and 4, selectively operable MPDsub 66 includes a housing 78 having an outer surface 80 and an innersurface 82 that defines a valve chamber 85. A ball seat 88 is supportedin valve chamber 85. Ball seat 88 is coupled to inner surface 82 througha shear member 90. A tripping member 92 is fixedly mounted relative toinner surface 82 radially outwardly of ball seat 88. Ball seat 88includes a curvilinear surface (not separately labeled) that supports arotatable ball valve 98. Rotatable ball valve 98 includes a centralpassage 102 that may be selectively aligned with internal flow path 54and a recess 106 that is selectively receptive of tripping member 92.

Selectively operable MPD sub 66 is further shown to include anactivation member 110 arranged uphole of rotatable ball valve 98.Activation member 110 includes a ball engagement member 114 having acurvilinear surface (not separately labeled) that engages rotatable ballvalve 98. A conduit portion 117 extends axially outwardly and upwardlyfrom ball engagement member 114. A spring 119 extends about conduitportion 117. Spring 119 includes a first end 121 that engages a surface(also not separately labeled) within valve chamber 85 and a second end123 that act upon ball engagement member 114.

In operation, liner string 50 is run into wellbore 34 on work string 30with selectively operable MPD sub 66 in a closed configuration such asshown in FIG. 3. MPD system 58 remains active at surface to applypressure via an external flow path (not separately labeled) to wellbore34 to maintain a selected operating pressure. As liner string 50progresses downhole, fluids are displaced upwardly. Selectively operableMPD sub 66 ensures that those fluids do not progress up internal flowpath 54 beyond MPD system 58 and interfere with well operations atsurface system 12.

Once liner string 50 has reached target depth in wellbore 34,selectively operable MPD sub 66 may be opened and selectively operablesurge control valve 64 may be closed to circulate fluid down internalflow path 54 and back up an annulus defined between liner string 50 andannular wall 42 of wellbore 34 allowing conventional activation of linerhanger running tool 62 and any other tools below selectively operableMPD sub 66.

In an embodiment, pressure may be applied to rotatable ball valve 98 viaconduit portion 117. The pressure acts on ball seat 88 via rotatableball valve 98 causing shear member 90 to give way. Shear member 90 maybreak, shear, fracture or otherwise cease to be an impediment to themovement of ball seat 88. That is, once shear member 90 breaks, spring119 acts on ball engagement member 114 forcing rotatable ball valve 98downward. Recess 106 engages with tripping member 92 causing rotatableball valve 98 to rotate such that central passage 102 aligns withinternal flow path 54 thereby fluidically connecting MPD system 58 withsurface system 16.

Set forth below are some embodiments of the foregoing disclosure:

Embodiment 1. A managed pressure drilling (MPD) system comprising: awork string including one or more tubulars having an internal flow path,the work string supporting a liner string terminating in a liner float;a liner hanger running tool coupled to the work string uphole of theliner string and the liner float; a selectively operable surge controlsub arranged uphole of the liner hanger running tool; and a selectivelyoperable MPD sub positioned uphole of the liner hanger running tool andthe selectively operable surge control sub, the selectively operable MPDsub being operable to close off the internal flow path to fluid pressurepassing uphole from the liner float in a first position during MPDoperations and opens the internal flow path to fluid pressure after theliner string reaches a target depth.

Embodiment 2. The MPD system according to any prior embodiment, whereinthe selectively operable MPD sub includes a housing having an upholeend, a downhole end and a rotatable ball valve arranged between theuphole end and the downhole end.

Embodiment 3. The MPD system according to any prior embodiment, whereinthe selectively operable MPD sub includes an actuator member arrangedbetween the rotatable ball valve and the uphole end and a spring, thespring urging the actuator member toward the rotatable ball valve.

Embodiment 4. The MPD system according to any prior embodiment, furthercomprising: a shear member selectively holding the actuator member inthe first position.

Embodiment 5. The MPD system according to any prior embodiment, whereinthe selectively operable MPD sub includes a ball seat arranged betweenthe rotatable ball valve and the downhole end, the shear member securingthe ball seat to the housing.

Embodiment 6. The MPD system according to any prior embodiment, whereinthe selectively operable MPD sub includes a tripping member arrangedbetween the rotatable ball valve and the downhole end.

Embodiment 7. The MPD system according to any prior embodiment, whereinthe rotatable ball valve includes a recess receptive of the trippingmember.

Embodiment 8. A resource exploration and recovery system comprising: asurface system including a managed pressure drilling controller; a hostcasing extending downhole into a wellbore; a subsurface system includinga work string extending through the host casing into the wellbore, thework string including one or more tubulars having an internal flow path,the work string including a liner string and a liner float; a linerhanger running tool coupled to the work string uphole of the linerstring and the liner float; a selectively operable surge control subarranged uphole of the liner hanger running tool; a selectively operableMPD sub positioned uphole of the liner hanger running tool and theselectively operable surge control sub, the selectively operable MPD subbeing operable to close off the internal flow path to fluid pressurepassing uphole from the liner float in a first position during MPDoperations and opens the internal flow path to fluid pressure after theliner string reaches a target depth.

Embodiment 9. The MPD system according to any prior embodiment, whereinthe selectively operable MPD sub includes a housing having an upholeend, a downhole end and a rotatable ball valve arranged between theuphole end and the downhole end.

Embodiment 10. The MPD system according to any prior embodiment, whereinthe selectively operable MPD sub includes an actuator member arrangedbetween the rotatable ball valve and the uphole end and a spring, thespring urging the actuator member toward the rotatable ball valve.

Embodiment 11. The MPD system according to any prior embodiment, furthercomprising: a shear member selectively holding the actuator member inthe first position.

Embodiment 12. The MPD system according to any prior embodiment, whereinthe selectively operable MPD sub includes a ball seat arranged betweenthe rotatable ball valve and the downhole end, the shear member securingthe ball seat to the housing.

Embodiment 13. The MPD system according to any prior embodiment, whereinthe selectively operable MPD sub includes a tripping member arrangedbetween the rotatable ball valve and the downhole end.

Embodiment 14. The MPD system according to any prior embodiment, whereinthe rotatable ball valve includes a recess receptive of the trippingmember.

Embodiment 15. A method of performing a managed pressure drilling (MPD)operation comprising: performing surge reduction activities during amanaged pressure drilling (MPD) operations with an MPD system supportedon a work string including a liner hanger running tool, a selectivelyoperable surge control sub, and a selectively operable MPD sub arrangeduphole of a liner string; allowing fluid to freely flow through theliner string into the liner hanger running tool; dissipating surgepressure via the selectively operable surge control sub positioned belowthe selectively operable MPD sub without returning fluid up the workstring; and opening the selectively operable MPD sub and closing theselectively operable surge control valve after the liner string hasreached a target depth.

Embodiment 16. The method according to any prior embodiment, whereinopening the selectively operable MPD sub includes rotating a ball valve.

Embodiment 17. The method according to any prior embodiment, whereinrotating the ball valve includes applying pressure to an actuator memberto break a shear member and release a spring.

Embodiment 18. The method according to any prior embodiment, whereinapplying pressure to the actuator member includes applying fluidpressure from a surface system onto the rotating ball valve.

Embodiment 19. The method according to any prior embodiment, whereinapplying pressure to the actuator member includes forcing a ball seatarranged downhole of the rotating ball valve against the hear member.

Embodiment 20. The method according to any prior embodiment, whereinrotating the ball valve includes engaging the ball valve with a trippingmember arranged in the selectively operable MPD sub.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. Further, it should be noted that the terms “first,” “second,”and the like herein do not denote any order, quantity, or importance,but rather are used to distinguish one element from another.

The terms “about” and “substantially” are intended to include the degreeof error associated with measurement of the particular quantity basedupon the equipment available at the time of filing the application. Forexample, “about” and/or “substantially” can include a range of ±8% or5%, or 2% of a given value.

The teachings of the present disclosure may be used in a variety of welloperations. These operations may involve using one or more treatmentagents to treat a formation, the fluids resident in a formation, awellbore, and/or equipment in the wellbore, such as production tubing.The treatment agents may be in the form of liquids, gases, solids,semi-solids, and mixtures thereof. Illustrative treatment agentsinclude, but are not limited to, fracturing fluids, acids, steam, water,brine, anti-corrosion agents, cement, permeability modifiers, drillingmuds, emulsifiers, demulsifiers, tracers, flow improvers etc.Illustrative well operations include, but are not limited to, hydraulicfracturing, stimulation, tracer injection, cleaning, acidizing, steaminjection, water flooding, cementing, etc.

While the invention has been described with reference to an exemplaryembodiment or embodiments, it will be understood by those skilled in theart that various changes may be made and equivalents may be substitutedfor elements thereof without departing from the scope of the invention.In addition, many modifications may be made to adapt a particularsituation or material to the teachings of the invention withoutdeparting from the essential scope thereof. Therefore, it is intendedthat the invention not be limited to the particular embodiment disclosedas the best mode contemplated for carrying out this invention, but thatthe invention will include all embodiments falling within the scope ofthe claims. Also, in the drawings and the description, there have beendisclosed exemplary embodiments of the invention and, although specificterms may have been employed, they are unless otherwise stated used in ageneric and descriptive sense only and not for purposes of limitation,the scope of the invention therefore not being so limited.

What is claimed is:
 1. A managed pressure drilling (MPD) systemcomprising: a work string including one or more tubulars having aninternal flow path, the work string supporting a liner stringterminating in a liner float; a liner hanger running tool coupled to thework string uphole of the liner string and the liner float; aselectively operable surge control sub arranged uphole of the linerhanger running tool; and a selectively operable MPD sub positioneduphole of the liner hanger running tool and the selectively operablesurge control sub, the selectively operable MPD sub being operable toclose off the internal flow path to fluid pressure passing uphole fromthe liner float in a first position during MPD operations and opens theinternal flow path to fluid pressure after the liner string reaches atarget depth.
 2. The MPD system according to claim 1, wherein theselectively operable MPD sub includes a housing having an uphole end, adownhole end and a rotatable ball valve arranged between the uphole endand the downhole end.
 3. The MPD system according to claim 2, whereinthe selectively operable MPD sub includes an actuator member arrangedbetween the rotatable ball valve and the uphole end and a spring, thespring urging the actuator member toward the rotatable ball valve. 4.The MPD system according to claim 3, further comprising: a shear memberselectively holding the actuator member in the first position.
 5. TheMPD system according to claim 4, wherein the selectively operable MPDsub includes a ball seat arranged between the rotatable ball valve andthe downhole end, the shear member securing the ball seat to thehousing.
 6. The MPD system according to claim 2, wherein the selectivelyoperable MPD sub includes a tripping member arranged between therotatable ball valve and the downhole end.
 7. The MPD system accordingto claim 6, wherein the rotatable ball valve includes a recess receptiveof the tripping member.
 8. A resource exploration and recovery systemcomprising: a surface system including a managed pressure drillingcontroller; a host casing extending downhole into a wellbore; asubsurface system including a work string extending through the hostcasing into the wellbore, the work string including one or more tubularshaving an internal flow path, the work string including a liner stringand a liner float; a liner hanger running tool coupled to the workstring uphole of the liner string and the liner float; a selectivelyoperable surge control sub arranged uphole of the liner hanger runningtool; a selectively operable MPD sub positioned uphole of the linerhanger running tool and the selectively operable surge control sub, theselectively operable MPD sub being operable to close off the internalflow path to fluid pressure passing uphole from the liner float in afirst position during MPD operations and opens the internal flow path tofluid pressure after the liner string reaches a target depth.
 9. The MPDsystem according to claim 8, wherein the selectively operable MPD subincludes a housing having an uphole end, a downhole end and a rotatableball valve arranged between the uphole end and the downhole end.
 10. TheMPD system according to claim 9, wherein the selectively operable MPDsub includes an actuator member arranged between the rotatable ballvalve and the uphole end and a spring, the spring urging the actuatormember toward the rotatable ball valve.
 11. The MPD system according toclaim 10, further comprising: a shear member selectively holding theactuator member in the first position.
 12. The MPD system according toclaim 11, wherein the selectively operable MPD sub includes a ball seatarranged between the rotatable ball valve and the downhole end, theshear member securing the ball seat to the housing.
 13. The MPD systemaccording to claim 9, wherein the selectively operable MPD sub includesa tripping member arranged between the rotatable ball valve and thedownhole end.
 14. The MPD system according to claim 13, wherein therotatable ball valve includes a recess receptive of the tripping member.15. A method of performing a managed pressure drilling (MPD) operationcomprising: performing surge reduction activities during a managedpressure drilling (MPD) operations with an MPD system supported on awork string including a liner hanger running tool, a selectivelyoperable surge control sub, and a selectively operable MPD sub arrangeduphole of a liner string; allowing fluid to freely flow through theliner string into the liner hanger running tool; dissipating surgepressure via the selectively operable surge control sub positioned belowthe selectively operable MPD sub without returning fluid up the workstring; and opening the selectively operable MPD sub and closing theselectively operable surge control valve after the liner string hasreached a target depth.
 16. The method of claim 15, wherein opening theselectively operable MPD sub includes rotating a ball valve.
 17. Themethod of claim 16, wherein rotating the ball valve includes applyingpressure to an actuator member to break a shear member and release aspring.
 18. The method of claim 17, wherein applying pressure to theactuator member includes applying fluid pressure from a surface systemonto the rotating ball valve.
 19. The method of claim 17, whereinapplying pressure to the actuator member includes forcing a ball seatarranged downhole of the rotating ball valve against the hear member.20. The method of claim 17, wherein rotating the ball valve includesengaging the ball valve with a tripping member arranged in theselectively operable MPD sub.